The is a vital resource for technicians managing air-cooled screw chillers, such as the AGS and WGS series . These semi-hermetic, single-screw compressors are known for their asymmetric design and "Stargate" technology, which reduces noise by eliminating gas pulsations. Core Technical Specifications McQuay HSA compressors, such as the or , are built for high efficiency using R134a refrigerant.
Information on the "stepless" capacity control system, which uses load/unload solenoid valves and a slide piston to match the building’s cooling load precisely from 100% down to roughly 12.5%.
The original HSA compressors are aging (some units are 20+ years old). However, Daikin Applied continues to support them. In 2018, Daikin released , which updates several procedures in the original manual:
Even seasoned technicians make errors. The McQuay HSA service manual explicitly warns against these:
: For units with solid-state starters, verify settings like motor load amps and overload class. Troubleshooting Common Issues Potential Cause Recommended Action Failure to Load/Unload